Characteristics of Shaft Voltage and Bearing Currents

Efficiency and productivity improvements attainable through adjustable speed operation of process lines, air handling systems, water treatment facilities, paper and metal lines placed ac adjustable speed drives (ASDs) at the forefront of motor control. Simultaneously, modern high frequency switching power devices, employing bipolar junction transistors (BJTs) and faster insulated gate bipolar transistors (IGBTs), have produced unintended consequences on peripheral equipment, generally described as electromagnetic interference (EMI).